Tuesday, March 13, 2012

Who are these people that John Christy is refuting?

Maybe Christy is just being polite by failing to name the people he describes below:

"The dramatic claims about snow disappearing in the Sierra just are not verified," said Christy, a climate change skeptic and director of the Earth System Science Center at the University of Alabama in Huntsville. "It looks like you're going to have snow for the foreseeable future."

I'm somewhat surprised that people were saying that a massive mountain range with much of the elevation exceeding 10,000 feet was not going to have snow in the foreseeable future.  As kind and fair as Christy is, I think he should gently criticize by name the people who've said that, as well as the experts who've said that we currently see a decline in the Sierra snowpack.  Of course the article has a contrary expert:

Mike Dettinger, a climatologist and research hydrologist at the Scripps Institute of the U.S. Geological Survey, said Christy is picking and choosing data while misleading people about what climate change scientists are actually saying.
Recent studies by Scripps scientists have found that over the last 50 years the southern Sierra snowpack has gotten larger while the northern Sierra pack has shrunk. Although they have predicted the overall state snowpack would decrease over time as a result of climate change, nobody has claimed that it has happened yet, Dettinger said. 
What's significant in terms of global warming, he said, is the fact that the snowpack has declined over three quarters of the western United States, an area that includes Montana, Wyoming and New Mexico. Scripps researchers, in coordination with Lawrence Livermore National Laboratory scientists, have concluded that 60 percent of that downward trend is due to greenhouse gases. 
"There is a popular conception that the snowpack has declined everywhere, but that is not what the science says," Dettinger said. "What we're saying broadly is that across western North America there have been declines in spring snowpack."
Might have been helpful to include this info near the beginning of the article instead of at the end.  Christy can always counter the criticism by naming names.  Go to it!

Also worth noting that he's combining different measurement systems over time to reach a conclusion, the exact thing that denialists criticize about temperature and sea level records used by climatologists.  So now we know it can be done, apparently.